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STEPHENVILLE (AP) – A prosecutor has said after the conviction of an ex-Marine in the killing of “American Sniper” author Chris Kyle and another man that “the biggest fallacy” of the trial was that post-traumatic stress disorder caused the defendant to commit the crime.

Erath County District Attorney Alan Nash said Wednesday that while Eddie Ray Routh got government PTSD benefits, doctors who evaluated him for trial, including the defense expert, agreed he didn’t have it. Nash noted Routh had a record of claiming PTSD to escape trouble.

PTSD wasn’t a trial focus. The defense argued Routh was legally insane from psychosis. Prosecutors said he knew right from wrong.

Kyle and his friend were killed after taking Routh to a shooting range. Routh’s mother wanted Kyle to help her troubled son.

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